I’m officially a muggle. At least that’s what “Team512”—known more colloquially as Margo Peterson among her colleagues at the University of California, San Francisco, where she works—playfully confirmed earlier today when I found her on the Hidden Garden Steps here in San Francisco’s Inner Sunset District.

Muggles, as readers of the J.K. Rowling Harry Potter series (or the Wikipedia “Muggle” article) know, are those lacking magical powers and magical blood. They are also, under the rules of the Geocaching game that brought Peterson to the Steps this morning, those not yet initiated into the pleasures of geocaching—whimsical searches that incorporate GPS technology into excursions introducing residents and visitors to places they might otherwise not be inclined to explore throughout the world. Geocachers who are successful at onsite and online searches find a variety of objects—the one on the Steps is a small ceramic turtle containing a metal cylinder with a piece of paper that geocachers use to document that they were there before also documenting their success online at Geocaching.com.

Margo Peterson

Peterson says she has more than 6,000 finds to her credit, including objects found in a cave outside of Livermore (here in the San Francisco Bay Area) and at the end of a “Vampire Empire” search that led her through part of the Chicago subway system. And although geocaching is, in her words, “a little nerdy,” it also offers the same sort of enticements that involvement in the Hidden Garden Steps project itself offers: an opportunity to be part of a playfully engaging—and engaged—community. Peterson says she knows of barbecues, coffee-house gatherings, and many other social events that have drawn geocachers together when they were not actively engaged in their onsite and online searches.